1. Field of the Invention
The present invention relates to an ink ribbon cartridge used for a printing apparatus for printing a recorded picture such as a video image or the like as a hard copy, a so-called color photograph or the like and which housed in is a spool shaft with an ink ribbon wound therearound.
2. Description of the Related Art
A conventional ink ribbon cartridge will be described with reference to FIG. 1 and FIG. 2.
FIG. 1 is a perspective view under a state where the ink ribbon cartridge is disassembled, and FIG. 2 is a perspective view under a state where the ink ribbon cartridge is assembled.
As shown in FIGS. 1 and 2, the ink ribbon cartridge consists of a lower shell 40, an upper shell 41 and an ink ribbon unit 1.
Firstly, a construction of the lower shell 40 will be described. The lower shell 40 has a pair of semicircular spool shaft receiving units 42, 43 and both the end portions of both the spool shaft receiving portions 42, 43 are integrally connected with wall plates 44, 45, respectively. One wall plate 44 is provided with bearing apertures 46, 47 in which are pivotally received drive side shaft portions of both spool shafts of the ink ribbon unit 1, which will be described later on, and the other wall plate 45 is provided with U-letter shaped bearing portions 48, 49 corresponding to the bearing apertures 46, 47, respectively by which driven side shaft portions of both the spool shafts are pivotally received. A portion between both the above-mentioned spool shaft receiving portions 42, 43 is made as an opening portion 50. Besides, ribs 51, 51 are formed on outer side edge portions of both the spool shaft receiving portions 42, 43, respectively.
On the other hand, the upper shell 41 has an opening portion 52 the same size as the opening 50 in the lower shell 40 through its upper surface, and constitutes a housing of the ink ribbon cartridge after being combined with the lower shell 40. In addition, the upper shell 41 has also ribs 53, 53 formed on its outer side surface portions.
On the other hand, the ink ribbon unit 1 is constructed as follows. There are provided a ribbon supply spool shaft 2 wound up with an unused ink ribbon 3 and a number 4 is a ribbon takeup spool shaft 4 for winding a used ink ribbon. At one end portions of both the spool shafts 2, 4 there are respectively provided hollow drive side shaft portions 5, 6 by way of flanges 5a, 6a. On internal circumferential surfaces of the drive side shaft portions 5, 6 are respectively formed projections not shown in the figure which will engage with drive shafts of the printer.
Further, at the other ends of both the spool shafts 2, 4 there are respectively provided driven side shaft portions 7, 8. Further, a ribbon code reading ring 9 is rotatably supported by a shaft portion between the ribbon supply spool 2 and the driven side shaft portion 7.
In order to assemble the ink ribbon cartridge having parts constructed as above, firstly the drive side shaft portions 5, 6 of both the spools 2, 4 of the ink ribbon unit 1 are pivotally received by the bearing apertures 46, 47 of the lower shell 40 respectively, and then the driven side shaft portions 7, 8 are pivotally received by the driven side shaft bearing portions 48, 49 respectively to thereby house both the spool shafts 2, 4 in the spool shaft receiving units 42, 43. Thereafter, the upper shell 41 is united with the lower shell 40, and then the contacting portion of the ribs 51, 53 of the both shells 40, 41 is melt-fixed by a spot welding 54 or the like, whereby the ink ribbon cartridge is constructed as shown in FIG. 2.
Accordingly, a part of the ink ribbon 3 which traverses from the ribbon supply spool shaft 2 to the ribbon winding-side shaft 4 is exposed from the opening portions 50, 52 of both the shells 40, 41. Further, the ribbon code reading ring 9 is made to be exposed outside partially from recesses 40a, 41a formed respectively in both the shells 40, 41.
By the way, when the above mentioned conventional ink ribbon cartridge is loaded on a printer apparatus and used for printing action. When the ink ribbon is used up once, the ink ribbon cartridge can not be reused, resulting in being discarded. There is no damages whatsoever, however, to functions of the lower shell 40 and the upper shell 41 which constructs the housing of the cartridge. Therefore, it is possible to reuse the cartridge if the ink ribbon unit is taken out from the inside of the shells, but in view of a product state of the cartridge it is difficult to separate both the shells 40, 41 because they are melt-fixed. Even if they are separated, damages are done to the shell itself, so in the past there has been no other way but to dump all the ink ribbon cartridge, which is not economical.
Further, at a time of dumping the ink ribbon cartridge, sorting out the used ink ribbon, the shells and the spool shafts has to be done after disassembling the given cartridge, so the sorting-out work therefor is troublesome. At the same time, when burning, the shells an incinerating furnace is necessary capable of enduring a high temperature, which has demanded much trouble with the dumping process.
On the other hand, an ink ribbon cartridge with a replaceable ink ribbon unit relative to a housing of the cartridge has been on the market, but the exchange of the ink ribbon unit requires much time in the replacing work and hence in some cases, quality of the ink ribbon may be impaired.